Switch



Nov. 29, 1932. P. E. cooK 1,889,514

SWITCH Original Filed Nov. 23. 1927 2 Sheets-Sheet l Nov. 29, 1932.

SWITCH Original Filed Nov. 23, 1927 2 Sheets-Sheet 2 Inventor Perc E.Caok BW* #n Patented Nov. 29, 1932 UNITED STATES PATENT OFFICE PERCY E.COOK, 01T' HADDONFIELD, NEW JERSEY, .ASSIGNOR, BY MESNE ASSIGNMENTS,

T0 ALLIS-CHALMERS MANUFACTURING COMPANY, OF MILWAUKEE, WISCONSIN, A.

CORTORATION 0F DELAWARE SWITCH @riginal application led November 23,1927, Serial No. 235,82. Divided and this application filed January 27,1930.

'l his invention relates to improvements in switches for transformers,and is a division of my co-pending application Serial No. 235,- 182,tiled November 23, 192?.

Primarily, the invention is a safety device, the object of which is toprevent any manipulation of the electrical connections of a transformerWhile the transformer is energized by current tloiving into any of itscoils.

In electric lighting and power line systems for communities utilizingelectric current in large amounts, the so-called network system, inwhich the low-tension es for a number iirl of transformers so ivired asto intercommnnicate, is becoming increasingly inijortant. ldlhen such asystem is employed, there is danger involved Working on the transformersin the group when current is being ted into any one or more of theothers of the grou-p, for, even though the high-tension side o' aparticular transformer be disconnected -from the high-'tension line, thehigh-tension coil may be en ergized by current flowing in thelow-tension coil. In other Words, 'the transformer then becomes a stepuprather than a step-down transformer.

@ne or" the objects of the present invention is the provision of meanswhich shall make it impossibler for a Workman or vany one else to movethe switch Tvhile current is flowing in the lovv-tension side ot theline as the result ot induction in that particular transformer or anyother transformer of the group. 'l`he workman will, ot course, notattempt to perform any operations upon the transformer with the switchin operative position, and/il he cannot move it from that position, heWill knovv that current is passing through the transformer in either onedirection or the other. lrle Will then be forced to take the necessarysteps to clear the transformer entirely. y Another object is theprovision ot means for short-circuiting and grounding the primary coiloit the transformer, or ot merely breaking the circuit between the coiland the high-voltage line.

A further object is the provision of a magnetic loclr :for holding theswitch in a given Serial No. 423,629.

position Whenever the secondary of the transformer is energized.

Still another object is the provision of a switch mechanism or" the kindreferred to, employing a plurality of sets ot contacts, and bridgingmeans for said sets embodying a movable element and magnetic lock forthe latter.,

Other objects and features of novelty Will .,ppear as l proceet^ withthe description of vhat embodiment of the invention which, for thepurposes o the present application, l

'rated in the accompanying drawings, i` which Figure l is a verti of anele tric switch myinvJA n;

Fig. is an elevational vievv of that portion of the apparatus whichwould normally be located outside the Wall or top of a transtormerg Fig.3 is a transverse sectional view taken substantially on line 3 3 ot Fig.l;

lT ig. l is a view of the selector cover which closes the opening in thetop of the casing of a transformer;

lig. 5 is a vertical sectional detail View taken substantially on line 55 of F ig. 1, and illustrating the magnetic lock;

Fig. 6 is a diagram of electric circuits illustrating the use of theinvention;

Fig. 7 is a cross-sectional View of the magnetic lock, the View beingtaken substantially on the line 7 7 of Fig. 5;

Fig. 8 is a plan view ot' a locking ring used in carrying out theinvention;

Fig. 9 is a cross-sectional detail view, this 'View also being takensubstantially on the 12 by means of -which metal hangers 13 aresupported. The hangers 13 carry an insulating tube 15, which may bebuilt of fiber or other suitable material having good insulatingqualities. Angular contacts 16, 17, 18

and 19 (see Figs. 1 and 6) have their vertical legs shaped to t theinner contour of the insulating tube 15, and have their vertical legssecured thereto by studs 20 and 21 which pass through openings formed inthe wall of the tube. The studs '21 are -continued far enough beyond thewall of the tube to constitute inding posts. Outside the tube 15 thebinding posts of contacts 17 are connected electrically, preferably by acopper bar or strap 22 which extends upwardly and is 'oined to one ofthe hangers 13, as shown in Arranged axially within the insulating tube15 is a longitudinally and rotatably movable element comprising rods 23,24 and 25 formed of suitable lengths of insulating material. Laminatedcopper springs 26 and 27 are interposed between the rods 23 and 24 andthe rods 24 and 25, respectively, each spring being adapted to form abridging connection between the corresponding arcuate contact 16 and oneof the contacts 17, 18, 19. These springs are mounted in arcuate clamps28 and 29, each of which is supplied with an integral hub portion 30 or31 for the receptin of one of the rods 23, 24, 25, suitable fastenings32 being set in the hubs and rods to hold them securely together.

The upper end of. insulating rod 23 has attached thereto by means of afastening 33 a metallic extension 34 comprising a collar 35l and areduced upper portion 36. The latter portion has a sliding and rotatingfit within the hub of a plate 37 which I term a selector cover. Thiscover 37 closes an'opening 38 on the top 10 of the transformer casing, agasket 39 being preferably interposed in order to maintain amoisture-tight joint. The periphery of the cover 37 is provided withpairs of spaced lugs 40 between which extend studs 41 that are threadedinto the top plate 10` and by means of which the cover is clamped inplace. At the upper end of the hub of cover 37, I mount a packing gland42 for excluding moisture.

As may be seen best in Fig. 4, the cover 37 has a series of upwardlyextending arcshaped projections 43,44 and 45 arranged in a circle, theprojections 43 and 44 having outwardly extending flanges 46 and 47,respectively, and the projection 43 having also a perforated lug 48.

The upper portion 36 of the movable switch element has a handle 49secured thereto by means of a pin 50. The lower part of the handle is inthe form ofa sleeve 51 which encloses the hub of the cover 37 and thepacking gland 42. This sleeve at one point 1n its periphery and at itslower edge has' an outwardly extending lug 52 which is adapted to fitwithin any of the three slots formed between the projections 43, 44 and45. lVhen the lug 52 is positioned in any one of these slots it tends toremainthere, due not only to and the movable switch element connected .A

therewith, it is necessary first to raise the same until the lug 52 islifted out of the slot in which it had been positioned. I provide a`means for preventing such lifting of the lug 52. In the presentinstance, this means consists of a locking ring 54, which surrounds thesleeve 51 and rides upon the tops of projections 43, 44 and 45, thisring being continuous except for an internal vertical groove 55 of asize sufficient to permit the projection 52 to move therein. ,Thelocking ring 54 may be rotated so as to bring the groove 55 intoregistration with any one of the slots between projections 43, 44 and45, and thus permit the lug 52 to be raised, after which the handle maybe rotated to turn the lug 52, carrying with it the locking ring 54 to aposition above one of the other slots, these slots corresponding, ofcourse, to the different positions of the springs 26 and 27. In one ofits angular positions the locking ring 54 is held against verticalmovement by hook-shaped projections 56 and l57 which extend around `andbeneath the projections 46 and 47 on the cover 37. In this same angularposition the lgroove 55 stands above the projection 44, that is out ofline with any of the slots between projections 43, 44 and 45. Thelocking ring is also provided with a perforated lug 58 abutting in theposition named against the perforated lug 48 so that a padlock may bemounted in the perforations of the two lugs 48 and 58 to secure thelocking ring against rotation. By

this means the handle 49 is securely locked authorized operation of theswitch.

We will now consider the apparatus ernployed for automaticallypreventing the operation of the switch when current is passing in eitherdirection through the transformer. On the lower end of rod 25 I secure,by means ofpins 60 and 61, a shoe 59 having a collar 62 at its lowerextremity. This shoe slides within an opening in a casting 63 whichbridges theo ening at the lower end of the insulating tu e 15. At oneend of the casting 63 there is supported an electromagnet core 64 ofinverted U-shape, around one leg of which is mounted a coil 65. Thecasting 63 includes a pair of depending arms 66, to the lower end ofwhich is pivoted a bell-crank 67. Qne arm of this bell-crank carries anarmature 68 adapted to bridge the ends of the core 64 of theelectromagnet, and the other arm carries a projection69 which is adaptedto overlap the collar 62 and prevent movement of the same.

Referringnow to Fig. 6, the wires of the high-voltage supply Aline areindicated at 70 and 71 and are shown connected to the contacts 19 of theupper and lower sets of contacts. The contacts 18 have no electricalconnections. The contacts 17 are shown joined together by the conductor22 which, as previously described, may consist of a copper strap asillustrated in Fig. 1. The conductor 22 also has a ground connectionthrough a conductor 13. The contacts 1G are joined by means ofconductors 72 and 73 with the ends of the high-tension or primary coil7-l of the transformer. The secondary coil 75 of the transformer haslead wires 7G and 77 extending therefrom which may have connections withother secondary coils of a network system. Shunted across the lead wires7G and 77 is the coil of the electromagnet referred to above.

In Fig. 10, the electrical connections are such that instead ofshort-circuiting and grounding the primary coil of the transformer, Ishort-circuit and ground the incoming high-tension supply lines, whichin this figure are numbered and 71 and are shown connected with thelarge contacts 1G.

vThe primary coil in this instance is connect-ed across the contacts 19by conductors 72 and 73. In other respects this figure is identical withFig. (i.

lVhenever there is current in the low-tension line wires 76 and 77, theelectromagnet coil 65 is energized, lifting the armature 68 and rockingthe bell-crank 67 to cause the projection 69 to overlap the collar 62and prevent upward movement of the rod 25 and the other movable portionsof the switch. In

nermal operation. the switch springs Q6 and 27 bridge the two sets ofcontacts 16 and 19 connecting the supply lines 70.v 71 or 70", 71 withthe transformer coil 74. -When the conl tacts 1S and 18 are bridged, thesupply lines `3 contacts 1G and 17 bridged, the supply lines aredisconnected and the primary winding 7 4 of the transformer issimultaneously shortcircuited and grounded. In the third position. asillustrated in Fig. 10, on the other hand, the primary circuit of thetransformer isopen and the high-tension feed line 70, 71 isshort-circuited and grounded.

Before any changes whatever can be made in the switch mechanism,however, the transformer must be disconnected from the supply line byother means not herein shown, and in case there is low-tension currentin the conductors 76, 77 due to action of other transformers in thenetwork, then the coil 75 must also be disconnected from the wires 7G,77. Otherwise, the electromagnet coil 65 will be energized and will lockthe movable switch element against upward movement. Following commonpractice in the art, automatic breakers may be employed in the circuit76,

77 to disconnect the coil 75 when current is not flowing in the primarycoil 7l, so that one operation only is needed to clear the transformerpreparatory to operating the switch of this invention. As previouslymentioned, tampering with the switch by anA unauthorized person may beprevented by the useof a padlock positioned in the perforated lugs 48and 58 thus holding the locking ring 54- from rotation and retaining thelug 52 inposition in one of the slots between projections 43, 4:4 and45.

Ubviously, the switch of the present invention may be used withtransformers other than those employed in an underground network system;the switch need not necessarily be mounted integral with the transformerbut may be separately housed; the switch in its different positions maymake connections other than those described above; more or less thanthree operating positions may be incorporated in the switch; and theswitch may be employed in connection with either singlephase orthree-phase circuits.

lfVhat I claim is: i

1. In switch apparatus, a switch member supported for movement indifferent directions, means operable to prevent movement of said memberin one of said directions independently of movement of the same irst inanother of said directions, and means operable to lock said memberagainst movement in said last-mentioned direction.

2. In switch apparatus, an operating niember supported for longitudinaland rotary movements, means operable to lock said member against rotarymovement independently of prior longitudinal movement of the same, andmeans operable to lock said member against longitudinal movement.

3. In a switch apparatus, a switch member supported for movement indifferent directions, means operable to prevent movement of said memberin one of said directions independently of movement of the same first inanother of said directions, and means operable to lock said memberagainst movement in said last-mentioned direction, said locking meanscomprising an element supported for rotary movement into and out oflocking position.

4. In switch apparatus, a switch member supported for movement indifferent directions, means operable to prevent movement of said memberin one of said directions independently of movement of the same irst inanother of said directions, and means directly engageable with saidfirst-named means to lock said member against movement in saidlast-mentioned direction and supported for movement into and out oflocking position.

5. In switch apparatus, an operating memloer supported for longitudinaland rotary movements, means operable to lock said member against rotarymovement independently -of prior longitudinal movement of the same,

and an element directly engageable with said A loci ingmeans to locksaid member against longitudinal movement and supported for rotarymovement about the axis of rotation of said member into and out oflocking-posi.- tion.

7. In switch apparatus, a switch member supported for movement indili'erent ldirections, means operable to prevent movement of saidmember in one of said directions independently of movement of the samefirst in another of said directions, means operable to lock said memberagainst movement in said last-mentioned direction, and electromagneticmeans operable upon being excited to hold said locking means in lockingposition.

8. In switch apparatus, an operating membersupported for longitudinaland rotary movements, means operable to lock said member against rotarymovement independently of prior longitudinal movement of vthe same,

` Ymeans operable to lock said memberagainst 5 longitudinal movement,and electromagnetic means operable upon being excited to hold saidsecond-named locking means in locking position.

9. A switch having a plurality of sets of contacts, a switch operatingmember supported for movement to three positions to selectivelyconnectelectrically one set of said contacts with either of two other sets ofsaid contacts orto isolate said one set of said contacts, andelectromagnetically actuated locking means operative when energized tolock said switch operating member -in one of said three positions. i

10. A switch having three sets of contacts, a. switch operating membersupported for movement to two active positions and one oil position,means operative upon movement of said member from one of said activepositions to the other of said active position to electricallydisconnect one set of said contacts from a second set of said contactsand to connect said one set of contacts to a third `set of saidcontacts, and electromagnetically actuated locking means for preventingupon energization thereof movement of said operating member from one ofYsaid active positions.

1l. A switch having three sets of contacts, means for holding the firstset of said contacts in spaced electrically connected relation and forholding the second set and the third set of said contacts ,in spacedrelation insulated from each other and from the first set of saidcontacts, 'means for causing the second set of said contacts to beelectrically connected selectively to the first set of said contacts orto the third set of said contacts, and locking means operable to preventsaid first mentioned means from causing the second set of said contactsto be electrically connected to the first set of said contacts.

12. A switch'comprising three sets of contacts, means for holding thefirst set of said contacts in spaced electrically connected relation andfor holding the second set and the third set of said contacts in spacedrelation insulated from each other and from the first set of saidcontacts, means for electrically connecting the second set of saidcontacts selectively to the first set of said contacts or -to the thirdset of said contacts, and .electromagnetically actuated locking meansoperative when energized for preventing the second set of saidcontactsfrom being electri-` cally disconnected rom the third set of saidcontacts.

In witness whereof, I hereto alx my signature this th day of January, A.D. 1930. PERCY E. COOK.

